e.g.TPO5 Lecture3：...But, let’s talk about Spectroscopy a little now just to cover the basics. What is Spectroscopy? Well, the simplest definition I can give you is that Spectroscopy is the study of the interaction between matter and light. 这个「topic+definition/explanation」一定要听懂，最好还能在笔记上记下关键词。（当然，也有话题词不那么明显的，这样的lecture的结构就稍微难以整理一点。）
e.g.TPO33 Lecture1：The great pyramid of Giza in Egypt might be the most famous building in the world. We know exactly when it was built: construction started in 2547 B.C.E., about four thousand five hundred years ago. We know who had it built: that was a Pharaoh Khufu. And we know who oversaw its construction: the Pharaoh's brother. We know so many things about it, but the funny thing is, we still don't know exactly how it was built. This picture will give you an idea of the size of the pyramid and the size of blocks it's made up of. About two million stone blocks were used to build the great pyramid, and they're incredibly massive. The average weight is two and a half tons. The problem that has puzzled scholars for centuries is how were these blocks lifted up the height of this massive structure and then fit into place and without the benefit of modern technology.Of course there have been a lot of theories over the centuries. 其实这就是常见的总起句式「several theories」「a few problems」「scientists have proposed several explanations」，下面的展开讨论部分就是具体展开这些theories、problems或explanations。
e.g.TPO33 Lecture1在总起「Of course there have been a lot of theories over the centuries」之后就逐个展开这些theories。
- The oldest recorded one 【theory1】 is by the Greek historian Herodotus...Well, so much for that theory.
- The next one【theory2】has to do with the use of a ramp...【theory2的问题】OK, so what now?
- Well, if you'd ever driven on a mountain road...So why not wrap the ramp around the pyramid【theory3】... Well, if you've got a ramp spiraling up from the base of the pyramid, those corners would be buried by that ramp during construction【theory3的问题】.
- Well, who says the ramp has to be on the outside of the pyramid? And now we get to the latest idea【theory4】: if the ramp were on the inside of the pyramid...
另外一种就是「总分总」的多个「分点」之间是直线型的时间关系，多适用于文科的内容。比如讲到某个作家的生平，一般都是「早年——青年——中年——晚年」，再比如讲到某种乐器的进化史，一般都是「起源——19世纪——20世纪——21世纪」之类的。比如TPO30 Lecture4：话题引入之后总起But really the instrument [electric guitar] we know today was the result of acontinuing development that started for our practical purposes in the 1920s. 然后就分阶段讲述guitar的发展史：
- The first guitars were wooden...
- the steel guitar was first introduced in the United States...in the late 1890s...
- Anyway, by the 1920s...
- Electrified guitars... around 1940...
直线时间递进型（文科话题）的总结没有明显规律，可能讲讲某作家的生平很励志，鼓励同学们努力，e.g.TPO1 Lecture1：No matter what, she never stopped painting. And now, Frantzen is doing extremely well. And her work is being shown all over the country. So I think most of us would be discouraged if we had to face challenges and difficulties like that. But what’s important is that you keep at it that you don’t give up. That’s what is really important to remember.
- 教授表示not sure：
e.g.TPO32 Lecture1： Clearly, more research needs to be done. Perhaps by some new scholars from this university? At least give it some thought.